5500 Watt element, what would cause it to burn out

[SchmuBrew]

Title kinda says it

3rd stripping run, burnt out the 5500

15g keg boiler
1 5500 watt element 240v
1 1500 watt element 120v
NEVER ran it dry
Power from dryer outlet, about 40' of #8 that leads to a 60amp sub panel. Nothing else connected to the sub panel

What's getting me is that (element still in the boiler, low wines in the boiler) is that it reading 10.1 ohms - which is what google is saying.

The only thing different from the 3 stripping runs of rum is that this was a cloudy corn wash.

This is literally the 4rth time I've fired it, other than a cleaning followed by a sac run


Thoughts ? Experiences ?